Mean-field analysis of a dynamical phase transition in a cellular automaton model for collective motion

A cellular automaton model is presented for random walkers with biologically motivated interactions favoring local alignment and leading to collective motion or swarming behavior. The degree of alignment is controlled by a sensitivity parameter, and a dynamical phase transition exhibiting spontaneous breaking of rotational symmetry occurs at a critical parameter value. The model is analyzed using nonequilibrium mean field theory: Dispersion relations for the critical modes are derived, and a phase diagram is constructed. Mean field predictions for the two critical exponents describing the phase transition as a function of sensitivity and density are obtained analytically.Comment: 4 pages, 4 figures, final version as publishe

Stat1 nuclear translocation by nucleolin upon monocyte differentiation

BACKGROUND: Members of the signal transducer and activator of transcription (Stat) family of transcription factors traverse the nuclear membrane through a specialized structure, called the nuclear pore complex (NPC), which represents a selective filter for the import of proteins. Karyophilic molecules can bind directly to a subset of proteins of the NPC, collectively called nucleoporins. Alternatively, the transport is mediated via a carrier molecule belonging to the importin/karyopherin superfamily, which transmits the import into the nucleus through the NPC. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we provide evidence for an alternative Stat1 nuclear import mechanism, which is mediated by the shuttle protein nucleolin. We observed Stat1-nucleolin association, nuclear translocation and specific binding to the regulatory DNA element GAS. Using expression of nucleolin transgenes, we found that the nuclear localization signal (NLS) of nucleolin is responsible for Stat1 nuclear translocation. We show that this mechanism is utilized upon differentiation of myeloid cells and is specific for the differentiation step from monocytes to macrophages. CONCLUSIONS/SIGNIFICANCE: Our data add the nucleolin-Stat1 complex as a novel functional partner for the cell differentiation program, which is uniquely poised to regulate the transcription machinery via Stat1 and nuclear metabolism via nucleolin

Overloaded adeno-associated virus as a novel gene therapeutic tool for otoferlin-related deafness

Hearing impairment is the most common sensory disorder in humans. So far, rehabilitation of profoundly deaf subjects relies on direct stimulation of the auditory nerve through cochlear implants. However, in some forms of genetic hearing impairment, the organ of Corti is structurally intact and therapeutic replacement of the mutated gene could potentially restore near natural hearing. In the case of defects of the otoferlin gene (OTOF), such gene therapy is hindered by the size of the coding sequence (~6 kb) exceeding the cargo capacity (<5 kb) of the preferred viral vector, adeno-associated virus (AAV). Recently, a dual-AAV approach was used to partially restore hearing in deaf otoferlin knock-out (Otof-KO) mice. Here, we employed in vitro and in vivo approaches to assess the gene-therapeutic potential of naturally-occurring and newly-developed synthetic AAVs overloaded with the full-length Otof coding sequence. Upon early postnatal injection into the cochlea of Otof-KO mice, overloaded AAVs drove specific expression of otoferlin in ~30% of all IHCs, as demonstrated by immunofluorescence labeling and polymerase chain reaction. Recordings of auditory brainstem responses and a behavioral assay demonstrated partial restoration of hearing. Together, our results suggest that viral gene therapy of DFNB9—using a single overloaded AAV vector—is indeed feasible, reducing the complexity of gene transfer compared to dual-AAV approaches

Global Diffusion in a Realistic Three-Dimensional Time-Dependent Nonturbulent Fluid Flow

We introduce and study the first model of an experimentally realizable three-dimensional time-dependent nonturbulent fluid flow to display the phenomenon of global diffusion of passive-scalar particles at arbitrarily small values of the nonintegrable perturbation. This type of chaotic advection, termed {\it resonance-induced diffusion\/}, is generic for a large class of flows.Comment: 4 pages, uuencoded compressed postscript file, to appear in Phys. Rev. Lett. Also available on the WWW from http://formentor.uib.es/~julyan/, or on paper by reques

A role of oligodendrocytes in information processing

Myelinating oligodendrocytes enable fast propagation of action potentials along the ensheathed axons. In addition, oligodendrocytes play diverse non-canonical roles including axonal metabolic support and activity-dependent myelination. An open question remains whether myelination also contributes to information processing in addition to speeding up conduction velocity. Here, we analyze the role of myelin in auditory information processing using paradigms that are also good predictors of speech understanding in humans. We compare mice with different degrees of dysmyelination using acute multiunit recordings in the auditory cortex, in combination with behavioral readouts. We find complex alterations of neuronal responses that reflect fatigue and temporal acuity deficits. We observe partially discriminable but similar deficits in well myelinated mice in which glial cells cannot fully support axons metabolically. We suggest a model in which myelination contributes to sus- tained stimulus perception in temporally complex paradigms, with a role of metabolically active oligodendrocytes in cortical information processing

Influence of hydrodynamic processes on the fate of sedimentary organic matter on continental margins

Understanding the effects of hydrodynamic forcing on organic matter (OM) composition is important for assessment of organic carbon (OC) burial in marginal seas on regional and global scales. Here we examine the relationships between regional oceanographic conditions (bottom shear stress), and the physical characteristics (mineral surface area and grain size) and geochemical properties (OC content [OC%] and carbon isotope compositions [13C, 14C]) of a large suite of surface sediments from the Chinese marginal seas to assess the influence of hydrodynamic processes on the fate of OM on shallow continental shelves. Our results suggest that 14C content is primarily controlled by organo‐mineral interactions and hydrodynamically driven resuspension processes, highlighted by (i) positive correlations between 14C content and OC% (and surface area) and (ii) negative correlations between 14C content and grain size (and bottom shear stress). Hydrodynamic processes influence 14C content due to both OC aging during lateral transport and accompanying selective degradation of OM associated with sediment (re) mobilization, these effects being superimposed on the original 14C characteristics of carbon source. Our observations support the hypotheses of Blair and Aller (2012, https://doi.org/10.1146/annurev‐marine‐120709‐142717) and Leithold et al. (2016, https://doi.org/10.1016/j.earscirev.2015.10.011) that hydrodynamically driven sediment translocation results in greater OC 14C depletion in broad, shallow marginal seas common to passive margin settings than on active margins. On a global scale, this may influence the extent to which continental margins act as net carbon sources and sinks. Our findings thus suggest that hydrodynamic processes are important in shaping the nature, dynamics, and magnitude of OC export and burial in passive marginal seas

Theoretical study of the absorption spectra of the lithium dimer

For the lithium dimer we calculate cross sections for absorption of radiation from the vibrational-rotational levels of the ground X [singlet Sigma g +] electronic state to the vibrational levels and continua of the excited A [singlet Sigma u +] and B [singlet Pi u] electronic states. Theoretical and experimental data are used to characterize the molecular properties taking advantage of knowledge recently obtained from photoassociation spectroscopy and ultra-cold atom collision studies. The quantum-mechanical calculations are carried out for temperatures in the range from 1000 to 2000 K and are compared with previous calculations and measurements.Comment: 20 pages, revtex, epsf, 6 fig

APPLICATION OF ADSORBENT "MIAMIKO-FIT" IN CHRONIC MULTIPLE MYCOTOXICOSIS IN PIGS

Однією із проблем сучасного свинарства є значна загибель поросят, що призводить до суттєвих економічних збитків. Причиною загибелі та вимушеного вибракування молодняку є інфекційні хвороби, які виникають на тлі ураження імунної системи, зокрема за виникнення мікотоксикозів.Оскільки близько 25 % фуражних зернових уражено пліснявими грибами, мікотоксини яких ушкоджують імунну систему та знижують резистентність поросят, тому актуальними є дослідження мікотоксикозів у тварин та розробка ефективних лікувально-профілактичних заходів.Проведено хіміко-токсикологічне дослідження фуражного зерна для годівлі поросят. Встановлено збільшену концентрацію мікотоксинів: охратоксину (ОТА), трихотеценів (DON) та зеараленону (ZON).Визначено імуносупресорний вплив мікотоксинів на поросят, що сприяє розвитку інфекційних захворювань та збільшенню загибелі молодняку.Наведено результати терапевтичної ефективності сучасного  сорбенту «Міаміко-фіт» у поросят за хронічного множинного мікотоксикозу, а також позитивний вплив згаданого вище препарату на рівень обміну речовин і корекцію функцій ушкоджених внутрішніх органів.Одной из проблем современного свиноводства является значительный отход поросят, что приводит к существенным экономическим потерям. Причиной гибели и вынужденной выбраковки молодняка есть инфекционные болезни, которые возникают на фоне поражения иммунной системы, в частности при микотоксикозах.Поскольку около 25% фуражных зерновых поражены плесневыми грибами, микотоксины которых повреждают иммунную систему и снижают резистентность поросят, поэтому актуальными являются исследования микотоксикозов у животных и разработка эффективных лечебно-профилактических мероприятий.Проведено химико-токсикологическое исследование фуражного зерна для кормления поросят. Установлено превышение содержания микотоксинов: охратоксина (ОТА), трихотеценов (DON) и зеараленона (ZON). Кроме этого установлено иммуносупрессорное влияние микотоксинов на поросят, что способствует развитию инфекционных заболеваний и увеличению падежа молодняка.Приведены результаты терапевтической эффективности современного сорбента «Миамико-фит» у поросят при хроническом множественного микотоксикозе, а также положительное влияние препарата на уровень обмена веществ и коррекцию функций повреждённых внутренних органов.One of the problems of modern pig farming is a significant death of piglets, resulting in considerable economic losses. The cause of death and forced culling of young animals have infectious diseases that occur against the background of the defeat of the immune system, in particular in mycotoxicoses.Because the about 25% of coarse grains amazed by saprophytic fungi, mycotoxins which damages the immune system and reduces the resistance of piglets, so are actual investigations mycotoxicosis in animals and the development of effective treatment and preventive measures.It was carried out a chemical-toxicological research of grain to feed pigs. Excess of mycotoxins: ochratoxin (OTA), trichothecenes (DON) and zearalenone (ZON) it was found. Established immunosuppressive effects of mycotoxins on piglets, which contributes to the development of infectious diseases and an increase in waste of young animals.Results of therapeutic efficacy of modern sorbent "Miamiko-fit" at piglets with chronic multiple mycotoxicosis, and the positive effect of the drug on the level of metabolism and correction functions of the damaged organs

Integrated teaching and software computer laboratory for the disciplines of svch@kr department

Описывается учебно-методическое и программное обеспечение компьютерных лабораторных практикумов, разработанных на базе следующих систем: в системе моделирования <pLabs на базе комплекса EduCAD; в Borland C++; на базе системы Sydney; в среде объектного программирования Delphi 5.Describes a teaching software and computer laboratory exercises, developed on the basis of the following systems: system modeling (pLabs based on complex EduCAD; in Borland C++; on the basis of Sydney; object programming environment in Delphi 5

The loss of histone H3 lysine 9 acetylation due to dSAGA-specific dAda2b mutation influences the expression of only a small subset of genes

In Drosophila, the dADA2b-containing dSAGA complex is involved in histone H3 lysine 9 and 14 acetylation. Curiously, although the lysine 9- and 14-acetylated histone H3 levels are drastically reduced in dAda2b mutants, these animals survive until a late developmental stage. To study the molecular consequences of the loss of histone H3 lysine 9 and 14 acetylation, we compared the total messenger ribonucleic acid (mRNA) profiles of wild type and dAda2b mutant animals at two developmental stages. Global gene expression profiling indicates that the loss of dSAGA-specific H3 lysine 9 and 14 acetylation results in the expression change (up- or down-regulation) of a rather small subset of genes and does not cause a general transcription de-regulation. Among the genes up-regulated in dAda2b mutants, particularly high numbers are those which play roles in antimicrobial defense mechanisms. Results of chromatin immunoprecipitation experiments indicate that in dAda2b mutants, the lysine 9-acetylated histone H3 levels are decreased both at dSAGA up- and down-regulated genes. In contrast to that, in the promoters of dSAGA-independent ribosomal protein genes a high level of histone H3K9ac is maintained in dAda2b mutants. Our data suggest that by acetylating H3 at lysine 9, dSAGA modifies Pol II accessibility to specific promoters differently